Even if making a new blog about this is wrong, I agree with the OP (about the blogs being annoying, not about the claim that a blocking feature would be useful).

Cheater blogs and the like are completely irrelevant for people (like me) who don't care about these things. It just takes up a lot of space in recent actions, and educational blogs sometimes get lost among these blogs, effectively decreasing the signal-to-noise ratio. I understand that cheating frustrates a lot of users, but there is a limit to how much you can complain about a certain issue, and to a user new to Codeforces, it might seem like Codeforces is a cheating-prevention site rather than a competitive programming site.

Eventually, it all boils down to how you view Codeforces rating. My view on it is that rating is simply a means to keep you motivated about problem solving, and sometimes a way to do a sanity check if you're not sure if what the other person is saying is trivial or not. If you think of it as something you earn by putting in your hard work and your goal is to get X rating in Y days by any means, and you feel that anyone else's performance using unfair means is going to hurt your performance, then you're doing everything wrong. If people who care so much about exposing cheaters put that much effort into competitive programming, their rating could be much more than what it is. Sometimes attributing your bad performance to the presence of cheaters is straight-up procrastination, you're guaranteed to get a better rating in the long run if you practice well rather than waste your brain-cells on complaining. At that point, you won't be affected by cheaters, since most of the cheaters are low-rated (note that I'm not implying that most low-rated people are cheaters), and you'd be doing better than them anyway.

The idea of having a "right" to rating (which I feel is what people who complain about cheaters have in mind) is very childish in my opinion, and if something on Codeforces makes it harder to learn competitive programming, then it's obviously bad for the site, and it makes sense to accommodate the users who want to learn something.

It would be great if there was a feature that could blacklist some keywords from the titles/content of the blogs that you see in recent actions, and maybe also filtering comments that satisfy this criteria (and this blacklist could be personal if possible). I understand that sometimes words like "cheaters" are found in the blog announcements when they announce that results will be announced after removing cheaters from the standings, so it might not be the best solution, but it can be worth considering.